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The evaluation performance of PDP (Policy Decision Point) plays a key role in the operation of a system. In order to solve bottlenecks of improving the PDP evaluation performance for large-scale policy sets, we propose an evaluation engine based on artificial neural networks, namely ANNPDP. We transform rules in a large-scale policy set described in the XACML (eXtensible Access Control Markup Language) into numerical rules. Evaluation networks are established and trained by the numerical rules. In order to ensure the accuracy, a misjudgment set is constructed for error corrections and stored by hash indexes. By simulating the arrival of requests, ANNPDP is compared with the Sun PDP, HPEngine, XEngine and SBA-XACML. The experiment results show that ANNPDP has: 1) high performance: if the number of requests reaches 10,000, the evaluation time of ANNPDP on the large-scale policy set with 100,000 rules is approximately 0.46%, 0.93%, 0.71% and 1.43% of that of the Sun PDP, HPEngine, XEngine and SBA-XACML, respectively, and 2) stability: as the size of the large-scale policy set and the number of requests increase, the evaluation time of ANNPDP grows linearly. ANNPDP can satisfy the requirements of an authorization system with large-scale policy sets

Light, a crucial environmental signal, is involved in the regulation of secondary metabolites. To understand the mechanism by which light influences carotenoid metabolism, grapefruits were bagged with four types of light-transmitting bags that altered the transmission of solar light. We showed that light-transmitting bagging induced changes in carotenoid metabolism during fruit ripening. Compared with natural light, red light (RL)-transmittance treatments significantly increased the total carotenoid content by 142%. Based on weighted gene co-expression network analysis (WGCNA), ‘red’, ‘darkred’, ‘yellow’, ‘brown’ and ‘midnightblue’ modules were remarkably associated with carotenoid metabolism under different light treatment. Transcriptome analysis identified the transcription factors (TFs) bHLH74/91/122, NAC56/78/90/100, MYB/MYB308, WRKY7/55, MADS29/AGL61, ERF043/118 as being involved in the regulation of carotenoid metabolism in response to RL. Under RL treatment, these TFs regulated the accumulation of carotenoids by directly modulating the expression of carotenogenic genes, including PSY, Z-ISO2, ZDS6, LCYB, LCYE, CHYB, CCD1-1/1-3, CCD4-2 and NCED2/3. Based on these results, a network of the regulation of carotenoid metabolism by light in citrus fruits was preliminarily proposed. These results showed that RL treatments have great potential to improve coloration and nutritional quality of citrus fruits.

Light, a crucial environmental signal, is involved in the regulation of secondary metabolites. To understand the mechanism by which light influences carotenoid metabolism, grapefruits were bagged with four types of light-transmitting bags that altered the transmission of solar light. We show that light-transmitting bagging induced changes in carotenoid metabolism during fruit ripening. Compared with natural light, red light (RL)-transmittance treatment significantly increases the total carotenoid content by 62%. Based on weighted gene co-expression network analysis (WGCNA), ‘blue’ and ‘turquoise’ modules are remarkably associated with carotenoid metabolism under different light treatment (p GGPPS2, PDS, Z-ISO, ZDS2/7, CRTISO3, CYP97A, CHYB, ZEP2, CCD1-2. Based on these results, a network of the regulation of carotenoid metabolism by light in citrus fruits is preliminarily proposed. These results show that RL treatments have great potential to improve coloration and nutritional quality of citrus fruits.

It is difficult for the Sinc-collocation method to solve directly boundary value problems in two variables with the mixed nonhomogeneous boundary condition. In this paper, a developed Sinc-collocation method with boundary treatment (SCMBT) is introduced. It is easy to treat mixed nonhomogeneous boundary condition for our method. The error in the approximation of the solution is shown to converge at an exponential rate. And the numerical results show that compared with the exiting results, our method is of high accuracy, of good convergence with little computational efforts.

Sinc collocation method is proven to provide an exponential convergence rate in solving linear differential equations, even in the presence of singularities. But in order to treat the derivatives on boundaries, people often relied on the finite difference method, which would be expected to limit the accuracy. The present paper develops a Sinc collocation method with boundary treatment for two-point boundary value problems. Numerical results show that the method can directly and efficiently handle the boundary derivatives.

In this paper, a highly accurate linearized method based on differential quadrature method is applied to the problem of pricing American better-of options on two assets, which is a free boundary and nonlinear problem in PDE. The present paper also efficiently treats the singularities at the initial values. Numerical results show that the method is efficient and stable.

Item does not contain fulltext Loquat (Eriobotrya japonica Lindl.) can be sorted into red- and white-fleshed cultivars. The flesh of Luoyangqing (LYQ, red-fleshed) appears red-orange because of a high content of carotenoids while the flesh of Baisha (BS, white-fleshed) appears ivory white due to a lack of carotenoid accumulation. The carotenoid content in the peel and flesh of LYQ was approximately 68 mug g(-1) and 13 mug g(-1) fresh weight (FW), respectively, and for BS 19 mug g(-1) and 0.27 mug g(-1) FW. The mRNA levels of 15 carotenogenesis-related genes were analysed during fruit development and ripening. After the breaker stage (S4), the mRNA levels of phytoene synthase 1 (PSY1) and chromoplast-specific lycopene beta-cyclase (CYCB) were higher in the peel, and CYCB and beta-carotene hydroxylase (BCH) mRNAs were higher in the flesh of LYQ, compared with BS. Plastid morphogenesis during fruit ripening was also studied. The ultrastructure of plastids in the peel of BS changed less than in LYQ during fruit development. Two different chromoplast shapes were observed in the cells of LYQ peel and flesh at the fully ripe stage. Carotenoids were incorporated in the globules in chromoplasts of LYQ and BS peel but were in a crystalline form in the chromoplasts of LYQ flesh. However, no chromoplast structure was found in the cells of fully ripe BS fruit flesh. The mRNA level of plastid lipid-associated protein (PAP) in the peel and flesh of LYQ was over five times higher than in BS peel and flesh. In conclusion, the lower carotenoid content in BS fruit was associated with the lower mRNA levels of PSY1, CYCB, and BCH; however, the failure to develop normal chromoplasts in BS flesh is the most convincing explanation for the lack of carotenoid accumulation. The expression of PAP was well correlated with chromoplast numbers and carotenoid accumulation, suggesting its possible role in chromoplast biogenesis or interconversion of loquat fruit.